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Erosion–corrosion of pipeline steel API-5L-X65 has in recent years become an important issue due to the high sand production rate and watercut in the maturing assets. The scope of using corrosion inhibitor to mitigate erosion–corrosion arises due to a number of industrial demands. The present study has been conducted to assess the performance of API-5L-X65 and the effect of corrosion inhibitor under high velocity (20 m s −1 ) jet impingement in four types of media containing 1.5 wt% sand particles: synthetic Forties brine, Forties brine with 5 vol% hydrocarbon (ISOPAR M), Forties brine and 100 ppm corrosion inhibitor, and Forties brine containing 5% ISOPAR M and 100 ppm corrosion inhibitor. Under jet impingement, the material loss was determined by gravimetric measurements and it is shown that the presence of corrosion inhibitor or hydrocarbon reduces the total material degradation of the pipeline steel in Forties brine. The most significant reduction in material loss rate for pipeline steel appears to result from the media containing both hydrocarbon and corrosion inhibitor in this study where an extremely strong interaction is observed. In situ electrochemistry combined with surface analysis and CFD simulations of the jet impingement have enabled the degradation mechanisms to be studied for different erosion–corrosion conditions.

The importance attached to the development of aluminum-lithium based alloys may be deduced from the fact that over the past seven years four major international conferences (1-4) have been devoted to these materials: The first was held at Stone Mountain, Georgia, in 1980 (1), and the most recent was in Paris in 1987 (4). This rapid sequence of conferences reflects intense research and devel­ opment activity within the laboratories of the aerospace companies, the aluminum companies, many universities, research institutes, and govern­ ment research establishments. One reason for this activity was the need for more fuel efficient aircraft because of escalating fuel prices during the 1970s: the addition of lithium to aluminum simultaneously reduces the density and increases the elastic modulus of the resultant alloy. A second and continuing impetus for the development of these materials comes from the requirements of military aircraft.